V. VASILEVA, P. MARINOVA and T. POPOVA
Institute of Animal Science, BG-2232 Kostinbrod, Bulgaria
VASILEVA, V., P. MARINOVA and T. POPOVA, 2009. Influence of the rearing system and sex on the adipocyte size and distribution in different fat depots in lambs. Bulg. J. Agric. Sci., 15: 257-262
The experiment was carried out with 30 lambs at the age of 75 days of the local Zapadnostaroplaninska sheep breed. The animals were divided in three groups according to the rearing system (indoors and on pasture) and the sex. 10 lambs were allowed to graze natural pasture, and additionally received concentrates of 250g/d/animal. The animals reared indoors received a commercial concentrate and hay.
The aim of the study was to compare the influence of the rearing system and sex on the adipocyte size and distribution in the perirnal fat and muscle tissue.
The rearing system led to a decrease of the content of the perirenal and intramuscular fat in the pastured lambs. Lower percentage of intramuscular fat content in m.Semimembranosus and the smaller proportion of adipocytes with average diameter were found in the male compared to the female lambs. Female unlike the male animals had a larger population of bigger cells within the range of 19-39 µm which is related to higher capacity for lipid synthesis.
The results obtained suggest that the changes in the lipid deposition and metabolism due to the rearing system and sex could lead to further improvement of the sensory traits and optimal composition of meat in relation to the human health and nutrition.